I use these just fine on my Mars 2 pro
ELEGOO 2 PCS Metal Resin Tank for ELEGOO Mars 3D Printer with FEP Pre-Installed and 2 Lids and 2 Allen Wrench, Resin Vat for ELEGOO Mars, Photon and Epax X1 https://www.amazon.com/dp/B07WGFF4K4/ref=cm_sw_r_cp_api_glc_fabc_b6x0FbJ5NY89F?_encoding=UTF8&psc=1
I switched over to a Elegoo Mars vat for my mono; bought this 2-packoff of amazon.
I got this one and it fits my mono 4k well enough and the mono and mono 4k should have the same size vats https://www.amazon.com/gp/product/B07WGFF4K4/ref=ppx_yo_dt_b_asin_title_o03_s00?ie=UTF8&psc=1. The plastic ones are cheaper but they're the same size so I'd imagine they'd work fine too.