If my eyes serve me correctly, it's a Crosman 357

Lol, so dumb I am...

Your right, it's a Colt Python airgun.

To anyone who owns one of these B&T MP5s, how are the stock internals? Same as all CA internals, in that some replacement is required?

If so, what needs replacement? I'm thinking of ordering myself one, and I'd like to get everything I'd need in one order.