You do not mention mileage. If mileage is not excessive your rings should be fine. The B230 engine is a workhorse and will run hundreds of thousands of miles and still maintain good tolerances. My 88 740 is now at 266K, has normal compression, burns oil at a rate of about 1qt per 3K miles. I had the head off at 190K miles because of an overheat and resultant head warp and possible crack. I replaced it with a used head. There was no sign of bore wear as indicated by no significant ridge at top of the cylinders. That is typical of these engines.

There is no way to check rings when just the head off. With head on the normal way is to run a compression test. If low and if a small amount of oil added to each cylinder raises the compression significantly this would indicate worn rings. Another indicator is oil consumption.

Most owners with a B230 engine that has wear to the point of needing rings or bearings would opt to install a used engine because they are easy to find and not that expensive. This a lot more practical than attempting to rebuild.

If head gasket leaks I strongly recommend you have head checked for warpage. Did you have an overheat?
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David Hunter