I forgot to mention I'm playing on a DS lite, If that matters.
This does, because some flashcarts don't work on newer DS models (DSi / 3DS) without software mods (cartridge blacklist).
what's a legit site to buy flash carts from
AliExpress - The Chinese Ebay, if you're frugal, patient and wary of certain sellers.
Otherwise your only option is Ebay or Amazon (which will be overpriced).
but I heard there's a lot of fakes.
They're all "fakes".
The only "genuine" one is the EZ Flash Parallel.
Maybe I could just settle for another acekard 2i then? where can I get one? do they still ship to Canada?
Ebay is your friend.
Don't expect to get one new.
This question has been beat to death in the past (with no one seemingly bothering to see if it has been answered before) with multiple answers.
The "best" flashcart you can get that is available on the market right now, is the DSONE.
These can sometimes come DOA with PSRAM errors, but the kernel is the best overall in terms of experience, and YSMenu can be used instead, should it come DOA.
Otherwise the only other flashcarts available are the Ace3DS / R4i clones. They all work basically the same and use the same base kernel (a very old version of WoodR4) and certain ones will brick if YSMenu is loaded.