These were made over 20 years ago-and are long since out of production. They were superseded about 12 years ago (ca 1999) by a Mk2 version which was even better-but lot more reliable and a bit heavier and of more conventional construction-but these too are long out of production and the Russian manufacturer is no longer involved with model engines in any way shape or form [a great pity]
Only likely place to find them is Ebay, or on the NFFS for sale items-maybe the MECOA wanted/for sale listings. I have four of various pedigree plus the 020 (which was a big disappointment!)

ffkiwi