If you’re after a small, aggressive high gain amp then I can’t think of anything better than a Dover DA-20. It might change your mind about EL84’s. To me it has really been the only low wattage high gain amp that impressed so far. Despite it being 20 watts and EL84, it sounds big and actually one of the tightest amps I’ve tried, only outdone in tightness by things like my CCV, Monomyth and possibly the Badlander, but haven’t AB’ed those 2 like I did with the ccv and Monomyth
Actually I think the Badlander 50 would be better now that you mention up to 50 watts plus it’s pretty compact size wise, but maybe a little over the budget you mentioned. The DA-20 might actually still sound fatter than the BL50, but still prefer the BL overall