I bought 58mm-72mm step up ring and a metal 72mm lens hood for my tamron 35mm-70mm lens. I already have a 58-77mm set up for it, but it just feels a bit 'big', for some odd reason. The 72mm hood does feel quite a bit smaller although you can barely see the difference in comparison to the 77mm one.
I've been trying to find some new 40.5mm filters for my fed 2, but I've had no luck, so I decided to experiment with a 40.5mm-46mm step up ring, 46mm filter and a slotted 46mm lens hood. While there is some viewfinder cut-off, it doesn't seem any worse than on my ricoh 500gx, so I've decided to go that way.