Well… I have some trouble to find the 1n5818… But I can find 1n5819 and 1n5817… I think the 1n5817 work, but it as a maximum reverse voltage of 20V… (cf http://www.robotroom.com/HBridge.html). The 1n5819 may work too, but I’m not sure…???
have you looked at the orderlist on smash’s order site? apart from that, farnell part no. 302-2754 apart from that, I don’t know, and I would also like to know if 1N5819 would work, as it is readily available in Australia! (Jaycar)