I see. Have you tried the memory foam ones that come with FX700?
The "usual suspects" would be Sony hybrids, which in my experience almost never fail in terms of fit (but then I did not have any issues with the original FX700 tips either). Having narrow bore, the downsize is that they too cut a bit of the sparkle - as small as this effect was, I did not want to give up an inch of the miraculous FX treble. Still worth giving them a try, you may hear things differently.
With my previous FX700 pair (which sadly was lost), I had also tried MEElectronics wide-bore tips - both regular and dual-flanges. Sound was ok, but due to the silicone being too soft and thin they would often fall off, so I gave up and quickly went back to the original JVC tips.
If I were you, I'd order a bunch of different tips and go through a trial and error process. Except high-end options such as Comply, tips are very cheap. You can even find Sony-style hybrids made by third parties (Nakamichi-branded are the first that come into my mind as I happened to have some around, but there are plenty of options on ebay and alike); these may be better for FX700 as most of them have a slightly wider bore than the Sony's.
This summarizes my experience with tips on FX700, I'll let the others share theirs.