Nice that you are getting it set up even better. One problem with replacement pickups is that the real Gretsch pickups are slightly narrower that standard humbuckers, so you'd probably have to go for humbucker-sized replacements or get some pickup adapter rings for fitting a smaller pickup in a humbucker rout, otherwise you may end up with gaps showing.

I don't know of any low-budget Gretsch style pickups, though you may find some used ones taken from Gretsch Electromatics on eBay. A cheaper alternative to TV Jones pickups would be Mojo pickups, a UK brand. They do a range of Gretsch style pickups, including a humbucker-sized one that looks like a Gretsch. https://www.mojopickups.co.uk/produc...kups/mojotron/. It's still £160 for a set but that's cheaper than TV Jones' are in the UK (at least £120 each). Mojo pickups always get a good review in the guitar magazines. Unfortunately it's basically a one-man operation and he's so busy that he's not taking orders at the moment in order to catch up, but worth considering if you do plan an upgrade.