Get a receipt as an eBay buyer

Sorry to say so, but it is not possible at all. You should save your purchase history from time to time locally in your computer if you wish to see them after a long time.

I believe some 3rd party eBay "sniper" software (which sometimes run as a web service, rather than desktop software) will do this sort of thing for you. The sniper software is generally used to automate the process of placing a bid in the last few seconds of an auction to increase the chances of a win.

From techradar's review of "The best free and paid eBay sniper software" it states that for "Auction Stealer" and "Auction Sniper":

...you can also place your bids in groups, so you can make bids on multiple auctions of the same type of item. When you win one, the others are cancelled.