I used to collect Bayonets. There's a huge selection, and there are expensive ones but also cheap soviet trash for mere dollars. So you can buy new shit every other week without losing much money while you're waiting for that wonderful, rare piece to pop up on Ebay.
I sold it all to a friend collector some time ago, but I had some good stuff. While not too rare, the SMLE, K98 and M6 bayonets were the nicest.
Swords require too much dedication and money.