Tron in Milford - Joe does a lot of guns for our club members.
But it wont be real cheap and may mean cutting wood - think about the cost on a pump gun. Wingmasters are nice; especially the older ones; but they are still a mass market pump gun.
Best case: a stock spacer or thicker recoil pad for LOP may help a lot on its own with no permanent alterations. Putting your cheek farther back on a sloped comb is same effect as adding drop; longer LOP will do this. Cheap and no permanent mods.
From there adding comb height [less drop] means adding a pad [cheap and removeable] or cutting the stock [expensive and permanant;] cast means heating and bending the wood.
You can chop off 1-2" of stock and add a fully adjustable buttpiece for drop, cant, and LOP but it wont change cast on/off.
You can also replace the entire buttstock with a fully adjustable version but that's likely more than that gun is worth.
Good Luck !!