2/3 of your credit score is based upon your management and utilization of open and active accounts.
That's why it's often recommended to have 2-3 open and active accounts reporting your history as the scoring algorithms will reward you for having more credit open. (the old 2 heads are better than 1 theory--in this case we are referring to revolving accounts)
Maybe a small credit card at Lowe's or Home Depot that you can open in the short term which will enhance your score through your purchase transaction?
You want your credit score to go higher, but you don't want to "tempt the demons" that are those creditors that will help you improve your score is like fishing without bait.