Your speaker is easy enough to drive that you have a some options under $1k, especially if you go used, which you should seriously consider. A lot depends on the qualities you're looking for in the sound and also the size and character of your room. I've not done much with tubes under 1k, so I'm tempted to just throw out some ideas which might be reasonable leads. Others will chime in with more solid experience.
https://www.usaudiomart.com/details/649707058-jolida-502brc-tube-integrated/
https://www.usaudiomart.com/details/649706802-black-ice-audio-by-jolida-fusion-f22-el34-integrated-s...
https://www.usaudiomart.com/details/649706727-rogue-audio-sphinx-v2-silver-w-two-remotes-plus-3-sets...
https://www.usaudiomart.com/details/649704208-rouge-audio-tempest-ii-super-magnum-tube-integrated-am...
https://www.usaudiomart.com/details/649699953-primaluna-prologue-one-tube-amplifier/
https://www.usaudiomart.com/details/649707058-jolida-502brc-tube-integrated/
https://www.usaudiomart.com/details/649706802-black-ice-audio-by-jolida-fusion-f22-el34-integrated-s...
https://www.usaudiomart.com/details/649706727-rogue-audio-sphinx-v2-silver-w-two-remotes-plus-3-sets...
https://www.usaudiomart.com/details/649704208-rouge-audio-tempest-ii-super-magnum-tube-integrated-am...
https://www.usaudiomart.com/details/649699953-primaluna-prologue-one-tube-amplifier/