Best DIY SET int/power amp?

I have this urge to hear an SET set-up in a small second system, but dont want to be dissatisfied with a novice, 8 WPC system that I'll have to upgrade after a short while, so am looking for suggestions for at least a 15 WPC system that I can build. Room size 12 X 12 X 10, listen to mostly classical, medium volume. Currently have Totem Sig 1, 87 db, 4 ohms. Budget about $1500-$2000 for amp.
Current small system: Jolida 502B level 1 mod with NOS tubes, Cairn-Fogg V2.0 with upsampler card, Acoustic Zen Double barrel biwire S/C, Empress i/cs, totems, VH P/Cs.
Ideally, an int amp, but if not possible, then a power amp.
Will I have to trade the speakers for single-drivers of 95 db or thereabouts?
Appreciate any input, as always.
Audio Note Kit 1 300B
Not DIY and not integrated but the Antique Sound Lab aq1006dt (I think). Its the one which is single ended with the 845 tube reviewed by Art Dudley. They put out a lot of power so you won't need to change to 95db efficiency speakers, they cost around $2995 for the pair.
If you're experienced check out designs at D.Douma's site, diyaudio & here & duncan & the diy listings.
Otherwise, do go for a kit -- some good ones at diyhifisupply & bottlehead (many others available too). Cheers
For 15Watt/87db/4 Ohm requirement, I would not pursue SET. For best results on SET, 94db/8 Ohm is the minimum I would go for. A friend of my used to own the ASL 1006 845 SETs. Big disappoint. Also, keep in mind that NOS 845s are around $1K each.