Hi Dave. any windblocker is good. I have an old mx5parts vinyl & velcro job i bought 10 years ago & it’s all i need. very efficient too (I’m 6’ 5"). it all depends on how much money you want to spend, £100+ or £10+ on s/hand.
I have a second hand original equipment deflector on my mk1 and it works really well. just a little buffeting around the part of my head where the hair used to be! I am 6ft too!
the other great thing about it is that it has pouches on it that allow you to stash a few cd’s MX5OC hats etc.
I think a windblocker, whatever type, is needed. It makes driving these cars a lot more comfortable and in the winter a lot warmer. The MK2 type that folds down is probably the best for bot a lot of money.
I to brought a Mk1,March 97, MX5 last July. First time the wife and I went out in it, her was all over the place.
Went on Ebay and brought a mesh black wind deflector with a padded type frame. I paid £3.75 but what the heck. Collected from a another MX5 owner who lives in Brownhills. It only took 5 minutes to fit and it works great, wife also happy with it. Enjoy driving the mx5 I have.