Any breed guesses on Leo?

I can definitely see the Irish Wolfhound.  His color and the double dew claws sound like Pyr.  What do you mean by a large Lab?  Just trying get an idea at his height, everyone's opinion of large is different. I love his unique look!

Well, we've never actually measured him, so I'm not sure how tall he is. He is significantly shorter than our Anatolian.

His head is VERY wolfhoundish (is that a word?[]).  As for the rest...?

It would be so incredibly unlikely that an Irish Wolfhound would find a Pyr that I find it hard to believe. More plausible is a fortuitious combination of terrier and collie and livestock guardian genetics that you'd find in many rural areas. That
"bearded" coat is dominant so it could be several generations removed.

Also, the Wolfhounds I've seen were just plain massive - not like a Pyr of course, but they are definitely not as elegant as many sighthounds. A cross of those two breeds would not moderate the Pyr heaviness or size much at all.

How old is he? Wolfhounds only live to be between six and eight years old, sadly, and they are highly prone to cancers and other large breed problems (possibly another reason you just don't see them out there breeding randomly).

Pyrs can live longer but they are one of the shortest-lived livestock guardian breeds, maxing out around eleven. A more motley mix than straight Wolfie/Pyr would mean a much better and longer life for your boy - though less romantic than thinking he's a Wolfhound, lol.

He's really beautiful!

Well, he's a rescue, so we don't necessarily know how old he is, but the guesstimate is 7-8 years, and he's fairly "old" at that age, with bad teeth and moderate arthritis.

I agree that Wolfhound would be unlikely, but his tail really makes me think the unlikely may have happened, because I've never seen that type of tail in another breed. I wish I could find a picture that shows it. The Wolfhound is really the unlikely part here--there are Pyrs all over the place.

I'm curious about your thoughts re: terriers and collies. What types of terrier and collie? Leo seriously has the best disposition of any dog I've ever known, and it would be worth it to me to know his breed make-up so I could seek out others of those breeds in the future.

look at some pics of assorted lurchers, especially the terrier/collie/greyhounds. They look a bit like your boy, and are reported to have lovely temperaments.

Brookcove, I'm going to start following you around.  Your posts are always so nicely laid out and informative. 
 
It's a long shot, but she kinda sorta looks like a Wheaten, although Brookcove's explination is more likely. 

He's like 10X the size of a Wheaten, though.

The lurcher pictures are really interesting. I could definitely see him being one of those mixes They are all a lot thinner and more slenderly built than he is, though.

The lurcher is not really a breed, it's a sighthound crossed with a working dog, so there's quite a bit of variation. 

First generation labradoodles have wiry coats an look wolf-houndy, with a beard too... they often seem to have longer ears, though. Maybe standard poodle/husky? 

I thought about labradoodle too - that's a good possibility. But I think the appearance may be more superficial as the coat is a bit different from a terrier, with the terrier being more wiry?

Someone posted about the lurchers, which is what this dog really reminds me of most. As to what kind of terrier - anything that carries that wiry coat - from a Jack Russell up to a Giant Schnauzer - would do the trick. Don't imagine the terrier breeding the Pyr - I'm picturing a second or third generation cross, whether random bred or purpose bred (like the lurchers or labradoodle).

You're very kind, fuzzdomestic.[]

ETA: Just thought about the ears. Those ears are typical of Aussies and Border Collies and some English shepherds (though an ES would be less likely in Pennsylvania). And of course sighthounds have those ears (that's where the BC got them). Terriers tend to have erect or half-erect ears also. They would definitely not come from a mix that included only lab, poodle, and Pyr as all those have soft, pendulous ears.