I have this same problem with my Leedy floor tom. It has straight legs as well.....I purchased a couple of different kinds of replacement feet to experiment, as the foam rubber pads under the legs were not that practical in regular use. I tried out the Pearl REGULAR R-5 feet, not the air ones as those looked just too goofy for my taste. The regular Pearl R-5s were better, more resonance than the regular tips (which were original and seemed to be petrified when I finally removed them!) but not like it is when you lift it off the floor. So I also ordered a set of the Gibraltar "floating feet" # SC-FFT......they seem more like regular looking tips, but incorporate the Pearl air feet idea. BINGO! These things work great! No difference in sound now when the drum is held by the rim in my hand or sitting on the floor on the feet!
No need to buy replacement legs or fancy RIMS mounts! And these were about $6.00 plus shipping off of ebay. The Pearl R-5s were about $4.50 off of ebay. I'll keep the Pearls around as spares, but I highly recommend the Gibraltar tips as they work and don't look as goofy as the Pearl air tips. BTW, the heads are Remo Fiberskyn 3 ambassadors top and bottom tuned medium....has a nice deep Krupa type floor tom sound now.....think I'm off to play along to Sing, Sing, Sing...... :D