those are k20 type motors very common for use in servos. you will notice by coincidence similar ones in the servo mod thread i just mentioned. doubtful they can use a prop as big as the ones in those bidproduct photos but i think our smaller walkera. wlt, udi props might work. they do have 1mm shaft. only way to tell is try it. $8 (40 cents ea) is very cheap but you have to be careful of his shipping charges. sometimes only a dollar or two and other times 5-10 bucks. if shipping is not too much i might try those on my next order.