if it was me and my budget could strrtch to it would get an unground one cause your crank will be not far off it end of life if you have to regrind again. Believe you can go to .75 on them. Not it just get away with a polish/clean ?

Put in google cosworth crank grind sizes or something along those lines. It brings up an old post off here where someone actually lists the different sizes of grind. All you need then is to borrow some measuring calipers and you know where your cranks at in its life.

If buying a new one be careful and measure yourself, don't take other peoples word for it.
Had a guy near me was selling one and said it just wanted a grind and good to go.

Totally shit himself when i pulled out the calipers as he knew it was scrap. was on its last grind and was well and truly dead.