PSU for a build

Sup guys, I took from an E dumpster an office pc (it works), with an Intel i5-8550, 8gb of ddr4 ram, and I have to get new storage (the motherboard is a msi h310m pro-vdh plus. I got a used rx 6750xt for 225 Euro. I was looking to get a PSU and was wondering what I should get. In 3 or 4 months I was planning to upgrade mobo and cpu (was thinking of going am5 with ryzen 5 9600x). I've seen modular psu costs a lot more than the normal ones. I'd like to stay under 130/150 euros if possible. Anyone can help? Thx in advance