tips on finding tainted fusings

I found a sweet corrupted body armour, and my goal has been to 6-link it. I've got six sockets using the tainted jewellers, but the problem is I have yet to find a single tainted fusing the whole League. I'm playing solo self found. The bench craft option costs 1500 fusions, which is possible to farm, and 1500 vaal orbs, which is an impossible amount of time required to farm. Meanwhile I found 2 tainted exalts.

I'm putting the beyond modifier on my maps.

Does anyone have any tips on to how to find enough tainted fusings to 6-link?

Should I go for high quantity and magicfind and low tier maps or higher tier maps? I can do level 16 maps without a lot of mods on them, but I'm not strong enough to do the lvl 14+ Maven invitation as an example.

there is a node on the tree that increases the drops of tainted currency...

I've only dropped 1 and played a lot of characters this league, though I haven't been targeting them.

Corrupted currency seems to drop pretty regularly when I am in beyond maps from what i've seen though.

As far as i'm aware beyond monsters still spawn based on proximity, so you want to juice up the maps as much as possible. Not sure about lvl but I would think juicing up what ever level you can clear quickly would be best.

Just dropped one on a T1 map, had 120 quant on the map it was medium juiced. I've been running low level maps for div cards, probably done about 8 beyond maps seems like i'm getting about .5-1 tainted currency from those map.

Have not encounter any of the big beyond bosses at this level, not sure if there is a min lvl req for them to spawn. When I was running t16's encountered those bosses pretty regularly and they seemed to be dropping at least 1 tainted currency item.