From the OK ENGINES NEWSLETTER:
"We will be re-introducing (with minor changes) our line of R series engines in 2007. This is a rear intake, reed valve engine which debuted in 1958 and was discontinued in 1964.
three models will be available in mid-april in quantities of less than 500 each. All engines packaged NIB in vinyl box with instructions.
OK CUB .049R Opaque tank, glow plug version $35.95
OK CUB .06R Opaque tank, glow plug version $39.95
OK CUB .049BR No tank, aluminum intake, glow plug $39.95"
Larry