Since it would be a "loan" that you would have to pay back to the 401(k), why not just incrementally fund an IRA. You can make as many contributions to a Roth as you like, as long as the total does not exceed $2000 in a tax year.

So, if you will be paying $150 a month to pay-back the 401(k) loan, you can instead send a $150 Roth IRA contribution, and after 12 months, your Roth will be fully funded. By the way, if you don't make the $2000 limit, no big deal - it's not required.

Good luck,
the hendrys