I agree with Nevada
In fact, I've done this with Toyotas, in the past, around the same vintage, early to mid 1990s
I've installed intermittent wiper switches on cars that weren't originally equipped with it
To be clear, I installed used Toyota parts, not new aftermarket. I got the swtiches at pick a part, so they were dirt cheap.
it was literally plug and play, no modifications required, whatsoever