Here's another county heard from:
Templar swords are not rare artifacts, or particularly powerful momentoes to the families of deceased Sir Knights (you can find them all over EBay). Indeed, my Commandery receives swords on occasion from the families of members who have passed on. Had the sword been a particularly powerful remembrance of a deceased family member, they (the family) would still have it locked up safe somewhere.
Now, what to do with your sword? Much depends on its condition. If the metal is not badly pitted (lots of little black spots on the blade), there are companies that will remove the old name from the blade and etch your name on it, putting it all back together. Then you functionally have an old sword with your name on it.
Should the blade be pitted or bent (standing a sword on it's point - even in the scabbard will eventually bend the blade somewhat) or otherwise unusable, these same companies will attach a replacement blade to the hilt. And, should you wish, you can pay to have your name etched on the replacement blade. Now you have a new sword with an old hilt and scabbard! These companies can also re-enamel the fancy enameled portions on the scabbard and/or hilt. Either of these options can be less expensive than buying a new sword, but really are not much less expensive in the long run.
You will have noticed that I have typed the word 'expensive' here several times. No matter how you do it, it's going to be pricey. Templar stuff never was cheap, but as membership within the organization has shrunk (just like in all forms of Masonry) the prices for new regalia have gone up. And the prices for refurbishing old regalia have gone up, too.
None of the Templar swords out there are particularly valuable as antiques or as collector's items. There's just too many of them on the market. So ... if you want to have an old sword re-bladed, I say go ahead (the price of having a new blade put in, etched with your name, is not much greater than that of having an old blade re-etched). But I have chosen to just use the old sword I got from our arsenal until such time as I can afford a new one of my own.
DO NOT TRY TO ALTER A SWORD AT HOME. I've seen too many attempts at this and they never come out looking right.