Mmm not good. i suspect you will have to get it welded up as a replacement maybe extremely difficult to find. do you have a FEL on your 1810?
That's a Japan-market model, not a US model.
Where's Leonard? He used to respond to this sort of request. Inquire at
Sheaffer's Town & Country Tractor
He knows contacts in Japan who can find anything. Prepare to pay for this specialized service.