I hope I'm not off base here (I don't own any Yaesu equipment). When I read this post I was curious what my iCOM 756ProIII had for a memory backup battery. It is CR2032. That is a common battery found on many PC motherboards for years. It could be Yaesu uses a (larger) '3032'. Might be worthwhile confirming before purchasing... "measure twice, cut once"
. Having said that, when I browsed the VX-5R manual on the Yaesu web site, I didn't seen any mention of any memory backup battery, certainly not like the ones mentioned above.