Two types of front glass were used in the 140 series. A windshield mounted in a gasket and a bonded windshield. You can tell immediately by the windshield trim. The gasket windshield has two large U shaped trim pieces with small joiners top and bottom center. The bonded windshield has an 8 piece trim, 4 straight sections and four corner pieces and a whole bunch of metal clips that rust out and will likely need replacing if you have a bonded windshield.

The bonded windshield is definitely available for replacement (I got one two years ago). I don't know about the gasket windshield. I think they are separate parts since I recall the parts book gave them separate numbers. As someone else noted, I think the bonded windshield is the same as used in the early 240 series.

Based upon feedback that I have had, skip the glass polishing kits. First off, super messy. You need to mask off or cover everything in site. Lots of splatter because it uses lots of lubricant for the abrasive. It will clean up candy-floss hazing; but, is not effective on deep scratches (sand under a wiper blade).