Since you like your F8 I thought this Plinius Class A amp might be worth mentioning as it has a low-bias mode so you can leave it on without killing your electric bill…
https://www.usaudiomart.com/details/650105469-plinius-sa-103-class-amps-amazing-powerful-class-a/
Here’s a McCormack DNA 225 that’s well below your price range but is a great amp that’ll power just about anything you throw at it…
https://www.usaudiomart.com/details/650106356-mccormack-dna-225-power-amplifier/
Best of luck.