Am new to forum . so my 140 harrison has a problem . in the gear selector is a little 22 tooth gear wheel as of last night it has 2 teeth missing . while cutting a screw something happend came out of gear bounced back and hit the gears . . questions 1 has anyone got a gearbox . 3 knobs across the top and selector at the bottom . metric . 2 anyone happen to have one .. a gear that is . 3 does anyone have part number or the spec of that gear . help much appreciated poor lathe needs help please .