I too owned a 380 blade and the previous owner had rebuilt the cylinders but it sounds like your's needs more than normal attention. My "uncle" is a retired hydraulics man and recently gave me his Sunnen AN 111 hone/stone set (I have borrowed my buddy's set before for honing engine cylinder bores and was tickled to get my own set). Uncle Duke had used the hones he gave to me for honing hydraulic cylinder bores....never occurred to me that this was an option until he brought this up. From what I understood, they often polished cylinders for better seal wear on higher end stuff but he specifically used this set to clean up pitting on damaged bores such as yours. It may be possible that you could have the pitting cleaned up by a local hydraulic shop or depending upon your access to the right tools, do this yourself.