If you're looking stay at stock springs but want an upgrade. Tein's has a line of replacement shocks. I just installed their adjustable model yesterday. However I'm on lowering springs but so far it seems like a good budget option aside from the Cusco if you don't need the height adjustability or want to mix and match springs. Otherwise maybe check out your local 86/brz facebook groups, someone always sells their OEM or Sachs struts for cheap.
https://www.tein.com/products/endurapro.html
Purchased from Rallysportdirect. I did wait until a 10% holiday coupon came up.
Endura Pro Plus (16 way adjustable)
EnduraPro (Non-adjustable)