Jacobsen Commercial 20

Very informative site, I am happy to have been accepted as a new member......This is my first post here and hopefully I can also be of some help to someone in the future. Here goes my first question.....I dumpster dove last spring and fished out this rotary mower. With a little bit of work I got it running like a bear. I have been looking for for some information as to the mfg. date of this Jake and the engine manufacturer. I have been to the Jacobsen site (found the parts schematic) but the techs. there have no information to give me. One tech sent me to the Homelite site which was a washout (no info available), another tech from Jacobsen recently said it maybe a 1990 to 1992 unit. Mower tags info as follows: Jacobsen Div. of Textron; Commercial 20; s/n: 032017 5372; engine tag: Jacobsen Textron; model: 123V; spec. no. : V51200; displacement: 123cc; hp/rpm: 4/3600. I think this may have a Subaru/Robin engine from my web searches. The gas tank says 50:1 mixture. There is no flywheel brake or bail on the mower handle, the deck is heavy gage aluminun, the wheels all have grease fittings, it is a rather heavy machine in nice shape. ......