I found the ones you mentioned as well as these other variations:

http://www.truetip.com/

And here are the Nintendo DS versions:

http://www.amazon.com/o/ASIN/B0007XS...AJRWQMS0NMJ002

Though they didn't get good reviews I think for situations like mine it might be a different story. Only concern is the fit. But geeze they are not expensive so I ordered a set of each type. Worst that case I am out $10.

Thank very much for the suggestion.