Free: Contests & Raffles.
You might be able to find a used vortex razor 16-48 in that range. (Older style) Do you need to get a tripod in that budget also?
Right now I'm not too worried about a tripod until the spotter ends up in my hot little hands.
Sports men's warehouse has the older vortex razor hd spotter on sale for 799...
https://www.bhphotovideo.com/c/product/276098-REG/Kowa_TSN_601_TSN_601_2_4_60mm_Spotting_Scope.htmlhttps://www.bhphotovideo.com/c/product/374107-REG/Kowa_TE_9Z_TSE_Z9B_20_60x_Zoom_Spotting.htmlYou cant go wrong with a Kowa made in Japan high quality glass. I can see 7mm bullet holes on paper @ 600 yards if the conditions are good. The price puts you just under 600. This spotter will blow away every thing in the 500-800 price range