Spendor S 3/5 with Antique Sound Labs Wave 8

You will need more juice than 8 watts with these. I suggest one of the more powerful push pull ASL tube amps. There seem to be plenty of used available a reasonable prices. Also you might want to check out the tubes forum on audioasylum. I use a 40wpc with my Spendor 2/3 and am very happy with the spund.

I would be cautious using a 8 watt amp driving those speakers. (84db/8 ohm) I see no problem w/ a tube amp
driving those speakers, but, higher power would be required,
IMO. Jolida has quite a few products that might serve your
needs. The only concern I have with those speakers and tube
amplification is that the sound could become too soft/mellow.
Depending on your tastes or room acoustics that might be just right. By all means upgrade your amplification.