As Clueless points out, they're Auricaps, not "audiocaps". There are a few archived threads on Audiogon about the Wave-8's, but more directly to your capacitor question, that issue is discussed in more depth in a couple threads on Audio Asylum. From what I've read, you want .47 uf caps.
Michael Percy audio sells them (www.percyaudio.com), he's reportedly a great source. Also, I bookmarked this page: http://www.vacuumtube.com/capacito.htm - they seemed to have a great price, but it's been a while since I've investigated pricing, availability etc.
BTW, I own two pairs of the Wave-8's and run them in my bedroom 3-channel surround (fronts + center - one amp unused as spare) system, un-modded, but with 1974 NOS Sylvanias - awesome sound and in no way believable at the price. I plan to mod them, when I get done with about a zillion other things... and yes, I'm quite happy with them the way they are, so I'm not in any hurry.
PS - The Wave-8's don't appear as regularly as Clueless opined. Also, if you're looking for naked just on price, those are also rarer here. I've been watching the 'gon daily for quite a few months, and only glimpsed one set of Waves (caged) in the past 3 months. I bought the set just previous to that (I'm done now!) I could've missed a couple listings, but no more than that. The last naked set I saw on the 'gon was about 6 mos. ago - the caged are much more common here. My (removable) cages are now wrapped in bubble-wrap in a plastic tote downstairs -- don't forget also that the caged version has an IEC receptacle, but the naked version is hardwired. I got an appreciable performance boost with aftermarket PCs with my amps that you couldn't experiment with if you bought the nakeds. Just my .02 - I'd get a caged/IEC version and store the cages.
If you're so inclined, a more expensive tube mono pair with the same goals (VERY cheap and huge value) is the Quicksilver mini-mite... about 3x as expensive, but also 3x more powerful at 25w and could also be interesting depending on what you're after (it can take KT88, EL34, 6550 etc). Seen a couple pairs here from $595 to $700. Anyway, just an amp that's caught my eye, but I've resisted buying since I gots what I gots and likes 'em.