Undersized Valve shims

Quick questions for you guys.

I have a set of Supertech followers that use Ø8mm shim, but the shims can only be purchased in the US and they end up to be very expensive (shipping and custom fees, delay, etc...)

In the other end, the 7.48mm shims are super popular on bikes so very easy to get and pretty cheap.

I still try to figure out if being 0.52mm smaller would make much of a difference and could cause any problems.

(the valve stem being 6mm)

Any of you ever tried that ?

I know of people who have done it on their Toyota's, I'm not sure how much smaller, would need to check, but didn't run into any issues, that I've seen posted.

What engine is this on?

It's for a Toyota 4AGE.

Supertech VS Stock

have you thought about shimless buckets?

Well I have the Supertech; no reason for me to buy another set of buckets.

And the Yaris buckets (that the only "shimless" option, in my knowledge at least, for the 4age) cost way more than a set of shims.

Shimless buckets wasn't an option in my case anyway simply because I have a few set of cams to tryout.