According to Douglas St Denny's Cameras of the People's Republic of China, the Hong Mei 1's date of manufacture was unknown to him, nor the number produced. However, he relates it was manufactured at the Changzhou Camera Factory in Changzhuo; was a 120 folding viewfinder with scale focusing; having a coated 5c, f/4.5 three element lens in three groups, with scale focusing from 1.5m to infinity; having a manually set, between the lens shutter, 1/10 to 1/200 sec plus B, self time, and PC synch. The serial number would be on a stamped piece of paper stuck to the back. It had internal masks for 6x6 or 645, with windows on the back, and an accessory shoe on the top plate. In the remarks, he related, "This folding 120 camera was very popular a few years ago. It filled the market left vacant when the Shanghai 202 ceased production. Though now out of production, it still can be found new on manhy smaller camera store shelves." His book was published in 1989.
EDIT: Oh, he translates Hong Mei as Red Plum Blossom. There was a thread here on RFF several years ago on Chinese cameras, including the Hong Mei as recall. There was also mention of St Denny's book. As I recall, a poster had several copies of the book, and I think that might be where I got mine.