Stop by your local Walgreens/CVS. Find the blood pressure tester. It usually checks your pulse too. If you have one, you'll be in.

Don't waste your money on an interview prep. Read a few gouges online, wear a proper fitting suit that is pressed and a conservative/professional tie (many will say red because of a projection of authority, just make it a normal color like red, blue, etc) Have your logbooks totaled and if there's any discrepancies be prepared to explain them.