Send out for repairs?

Hey everyone, I’m wondering what the cost is roughly aside from to and fro shipping to get the seals done on a C9A 22. ? I’ve never opened one up and I don’t have the special tools listed in the manual. I’m not so much worried bout the cost(reasonable in mind) as I am screwing it up. It has absolutely no pressure after an outing with my boy and a couple competitive teenage friends. Or am I making this to be more than it is? I haven’t opened it up yet so I don’t know if I have to resolder parts or what not
 
If it's a C9A like this one, with a removable valve, no special tools are needed and they are simple to rebuild. Driving out the roll pin's would be the hardest part and if you have a punch and a hammer, it's no problem, if not get a set at Harbor Freight. Really it's easy, watch a youtube vid about it. This is one of my C9A's, they are much fun!
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.... hey , lessismorr , if your pumper looks that shape and model above (gun color doesnt matter) , i can teach you how over the phone - that's why i left my phone number for you in my reply. green terror is right , the rifles crosman produced as benjis and dans after they acquired the benjamin, sheridan, sterling company in the early 1990's are easier to dissemble. many times i have to just order a new valve body from crosman for these , tho. it's a trip because they dont make those valves until you order them - or something weird like that. that gun is still in production - they should have lots of those big brass valves handy. most of the time i install a new valve stem for a benji disco as i rebuild those - shoots harder. contact me , lessismorr , maybe i can walk you thru replacing the pump cup ($2 part from crosman) and that'll suffice for now. - rane on (all the witch-hunters).
 
I apologize for not getting back to my post, life throws stuff at you here and there ya know? Yes my rifle looks a lot like the picture posted, just not as shiny. I got a seal kit for my pump master so I figure if I can get that back in working condition then I will take a shot at the Sheridan. And thankyou Rane I will like any help on the phone since it looks a lot more precision sort than the 760 does
 
Ok so I.rebuilt the valve with all new stock parts, I replaced pump cup. The pump cup fits snug but when I go to pump it the air blows out the end with the slide bolt closed(has new oring). The air tube is clean and clear of any dings/scratches. And valve has few light scratches but nothing measurable. I even wrapper thread in oring grooves to spread prongs out some but still cannot get air to stop coming out end. The one way has the tapered end facing the air hole. What could be issue?