A guy I know has offered to sell me his 20 gauge Purdey sxs made around 1930. It has two triggers, English stock, nice engraving, 26" barrels, rechambered to 2 3/4 & re-proofed, has a comfortable length of pull (for me - I'm 6'), original case etc. He's asking $25k. I've admired Purdeys for years but never considered purchasing one before. What are the things to look for on this type of gun? Is it fairly priced? Any advice would be greatly appreciated. Thanks!