The MR2 runs strut
inserts. You do not replace the whole strut body, just remove the upper spring perch and spring, the you removed the gland nut that holds the strut insert inside of the strut body. The inserts look similar to a normal shock, but they do not have a bottom mount, and the top of the shaft is threaded to fit inside the upper spring perch/strut top. Since you are not replacing the strut body itself, everything will still bolt up.
Now, concerning the Tokico struts... in the recent past there have been some questionable quality control issues, as they seem to have a good warranty, but a lot of people in the past few years have reported the struts failing in a very short amount of time. I purchased a set of four Tokico Premium Performance (blues) in 2002 and installed them along with ST springs, and they were perfectly good up until my car was totalled a couple years later.
Personally, the only strut insert I would buy for the MR2 to run with performance lowering springs would be the Koni Yellows, but those are kinda spendy (though if you go to
www.twosrus.com they are on sale for considerably cheaper right now) and may take some time to get dialed in correctly. Some people have reported to have good luck with the KYB GR-2 and AGX units, so you may want to check those out too.