Palladium is in the platinum family, so it's similar in hardness, color, etc. But it's not quite the darling of the jewelry industry the way that its sister metal is, so it's more cost effective. JT found this ring by DragonsBreath on Etsy that he really likes:
I really like it, too. I love the natural look of the hammered finish.
Titanium is an even more affordable option. It looks very "manly," so it's become quite popular in men's rings, and it's not hard to find titanium rings at major jewelry retailers these days. The downside to titanium is that it's so strong, it can't be resized once it's cast. So if JT gains or loses any weight, he'd have to get a new ring. But, as he put it, the cost of a titanium ring is so cheap, that it wouldn't be a very big deal to get it replaced. These two are from TitaniumKnights:
Both great, and at less than $100 each, he's right -- it wouldn't be a big deal to replace it if in a few years it no longer fit. Though that does seem slightly unsentimental, but is sentiment worth the extra money? Sometimes you just have to be practical. I won't love him any less with an inexpensive ring.