What do you like in an inexpensive tube integrated

Audio Space is manufactured in Hong Kong. Cayin is manufactured in China. Manley Stingray is manufactured in USA. You can call and talk to someone at Manley if you need advice or if you need service. The Stingray sounds much more powerful than its rating. It has a big relaxed sound that you get from high powered amplifiers with delicacy and detail. It's a no brainer.

Rogue Audio Cronus Magnum 90 wpc - USA built, excellent customer service if needed, or simply for asking questions

I second the vote for Rogue Cronus

Sophia Baby Electric,Eastern Electric MiniMax.

I just got a Stingray under your budget and am very happy with it. You don't mention the speakers you'll use it with, which will make a difference. I read that it's best suited for easy to drive speakers, and I agree based on the (only) 2 sets of speakers I tried mine on (my 98db benign 8-ohm-ers, and a friend's 92 db 4-ohm complex crossovers, etc.).
If you do look for a Stingray, go to the Manley webiste and get educated on the various changes from the late 1990s when it was introduced to just before the introduced the Stingray II (now at $5600 or so).
Made in California if that matters to you.