Dave 80 years young

Hi all, I am 80 years old and have owned a Sheridan Blue Streak since I was approximately 16 years old. This gun was manufactured some where's in the 1950's. After it set now used for many years I started to play with it about 5 years ago. Last year I installed a Pyramid Air kit, as it was not longer able to pump any pressure. Now it is as I remembered it for power. One thing I notice is that it shoots to the right. I have the rear site all the way to the left and it still shoots about 1/2 to 3/4 in to the right at about 20 feet. Either the barrel is bent or the front sight is bent. I will probable have to have a gun smith look at it. I do not have equipment accurate enough to sort it out. (Still trying different things) As I am getting older I am thinking about a PCP--except the pump and tank etc cost as much as a low price PCP rifle. I have considered trying to convert the Sheridan to a PCP. I have done some calculation from formula on the web and the Air reservoir will handle the pressure easily!!! If I calculated correctly. What I do not know if the Sheridan valve is sufficient to hold the pressure and not dump the whole reservoir on the first shot. Any advice /information in that area is more than welcome. Cheers .... The old young guy