Since GC is not available over here in Germany, i just pick JustMusic as my provider, if that is ok.
Last time i was in my local shop, they had a used Aguilar AG-500 for 500 bucks. I'd go with that if it was still there.
If not, i'd take the Markbass blackline head and whatever cheap 410 sounds best, over here they have hartke, laney, ashdown and a few minor brands for around 350.
That would cover the amp-side for around 650 and leave me with the choice of bass.
I'd pick a fiver. Possible candidates would be:
A Yamaha they had last time, i can not remember the name, but it was a decent player for 569,-
the Epiphone Thunderbird V in natural finish I played and liked a LOT more than all the Gibson ones they had, 449,-
Peavey Grind 5 - also cheap, also a lot better than i expected, for less than 500.
Since i did a lot of business with these guys in the recent past, i expect that they throw in a strap, a clipon tuner and cable,
So i'd be set and ready for something around 1000. So i'd either look for an upgrgade of amp or cab or bass and toy around a bit with what is possible.
If the amp and bass are fine, i'd take a Tech21 Bass Flyrig or quickly set up a small board with tuner, preamp and dirt.