Check the barrel...if it's a 3 groove, personally I've had no luck with accuracy using the black tin Benjamin pellets in those barrels.
She sounds good & solid to me. The Benj/Sher pellets will do OK in it, but JSB's will be more accurate. I still use BS pellets for hunting, though. Squirrels are scared to death to come on my property. JSB 13.73 will bump the fps up approximately 20fps, if that matters to you. JB Heavy's will slow it down a little. You can try all 3 pellets to see which you like the best. I saw a Model A on another air rifle site for sale, yesterday.
AoA has the 13.73's in stock or at least their website claims they do: https://www.airgunsofarizona.com/pellets/jsb-exact-.20-pellets/Call and they may well have the Heavy 15.89's too.
That's good data! Thanks for posting it up.I really enjoyed the article at the link, too. Now I have to go read the rest of them! Ride on,J~
The Model B will cost you more, if you decide to get one. There were not as many Model B's made as the Model A's. They both appreciate in value, though.