I completely understand that working with Biab can be a fun hobby and rolling your own is satisfying but if all you want is a good backing track for free, the first thing I would do is search YouTube. The second thing I would do is search for a midi file of it. Here's the first one that popped up on YT, there's probably others:

https://www.youtube.com/watch?v=Z3ejLdQZLfs

Download this, throw it into Real Band and have some fun with it. The YT one is audio but you can pitchshift it in RB to change keys. A midi one is dependent on whatever synth you use for the sound quality but you get full control over everything.

I just did a quick search and found one midi file, I can't post it because it has the melody in it. I played it in RB and it's typical of a freebie midi. It's not that good, the basic elements are there but it requires a lot of work to get it to sound right.

Bob

Biab/RB latest build, Win 11 Pro, Ryzen 5 5600 G, 512 Gig SSD, 16 Gigs Ram, Steinberg UR22 MkII, Roland Sonic Cell, Kurzweil PC3, Hammond SK1, Korg PA3XPro, Garritan JABB, Hypercanvas, Sampletank 3, more.