If I were you I would put new rings on the pistons to start with.
As for the cylinders, you mentioned a "wear" ring in the middle of the bores. That will probably be caused by the rings . Clean out the bores thoroughly but make sure you don't scour the cylinder wall, and check for wear.
Also check the top of the bores for a wear ridge at the top of the rings travel.
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<font color="blue"><i>1981 TR7 FHC Sprint (better known as 't Kreng)
1981 TR7 DHC (not very well known yet, but back on the road)
Also a 1980 TR7 DHC, 1980 TR7 DHC FI, 1981 TR7 FHC
http://tr7beans.blogspot.com/</i></font id="blue"></center>