I am the original owner of the RWS model 54 air rifle purchased it brand new around 20 years ago from Cabela's. At the time it was the biggest, most powerful air gun I could find on the market. With a good scope dialed in this rifle will consistently deliver the rounds right where you want them, notice my last photo from 55 yds, 10 rds and that is a 1.5" round circle. Weapon is not a break barrel but side lever to cock. Weapon as NEVER been stored cocked as they will wear out your spring and reduce the life. Weapon has also NEVER been dry fired, that will also damage the rifle. I have two scope mounting systems for it and the preferred is the long RWS version and cost an additional $50 from RWS. In some cases your scope might not fit and the other rings can be used. I've added an adjustable shoulder stock to this and also including the cleaning kit, with oil and soft gun case. I have about $700 tied up in this one.
I've killed squirrels as far as 65yds with this but really don't recommend doing more than 50yd as .177 looses much of its energy after that. Great weapon for youngster or adult. Weapon has always been stored in humidity controlled room and never out in adverse weather. Mostly just enjoy plinking and hunting with this guy. Weapon has been lightly oiled per instructions which I still have included. New these units are selling for around $750, see link below.
Selling for $450 and local pick up in Loudon / Lenoir City.
https://www.pyramydair.com/product/diana-54-airking-pro-air-rifle-beech?m=5271