Yes if you could post the length that would help. I have 211 wheels I want to put on a 210 and would be interested if the shank and ball sizes are what I need.
The shank size needed can be easily measured and calculated if the new wheels are readily available.
Take off one Lug bolt that is currently installed on your car and you can use it as the measurement tool.
While placing it into one of the new wheels and holding it firmly in place with one hand, measure the length of the threads sticking out the back side.
That measurement needs to be in the range of 17 to 20 mm's.
If it is in that range, simply measure the shank and you have your answer.
If the measurement was too short or too long, simply add or subtract until you get within the 17 to 20 range.
For Example, if you measure 30mm's, you need to subtract 10 to 13 mm's from the shank length of the test lug bolt.
And if you measured 10 mm's then you need to add 7 to 10 mm's to the shank length of the test lug bolt.
This is a general rule of thumb for all wheels/bolts.
As far as Ball size, if the wheel is drilled for 14M bolts, it is also machined for a R14 ball, and wheels drilled for 12M bolts will also be machined to take a R12 Ball.
I've seen posts saying that an American quarter has a radius very close to R14. Using modeling clay put into the ball seat and a quarter to scrape it out can prove it is R14 or not. I've not tried that, simpler to determine if the lug bolt hole is drilled for 12 or 14, the ball size follows whichever it is.
In your case it's as simple as "Do all 211's use 14M drilled wheels"?
If they do, you will need the type of bolt being sold in this thread, a great price if the length is right.