Holo Taco Hi-Def dupes?

Hello! I am pretty new to the community and just learning about all of the different techniques and brands/polishes available. I love the neon/retro/90s/Lisa Frank vibe just discovered Holo Taco’s Retro anniversary collection - and I’m desperately trying to find dupes or polishes for sale that aren’t $30+ per bottle.

One of the things that intrigues me the most about this collection is the ability to layer and blend colors (I love some of the gradients posted on this sub!). It seems like INLP has some similar sparkly jellies that may work as substitutes for the rest of the collection, but nothing I’ve found seems close to that Hi-Def neon jelly from Holo Taco.

I was also wondering, does anyone know if these limited release polishes ever come back for sale at Holo Taco? (I assume not but figured it doesn’t hurt to ask…). Also, if I were to layer two brands of jellies like INLP and Holo Taco would I still be able to get that rainbow gradient effect that I became obsessed with from this sub?

Thanks in advance for any advice!