seal

So I am going to attempt to replace the valve seals using the rope trick without removing the head as the head has been recently shaved and torqued down with ARP studs. I was a moron by not having the valve seals replaced while the head was off. So rather than paying a mechanic $800 to do this...

do USDM 2jz parts differ from jdm 2jz parts? i have a jdm 2jzgte engine from an aristo, if i needed a gasket or seal for example would i be able to get a parts from the dealer if i said it was for a 93-97 gs300 or supra??