Most gentlemen prefer to have their crest, rather than their arms, on a signet ring. Since the signet is worn on the little finger it takes quite a few knocks and bumps during the course of the year, and for that reason you should have it made up in 9ct gold-- anything else will be too soft to stand up to the rigors of day-to-day life.

I can, without hesitation, recommend The Heraldic Porcelain Company in London as an excellent source for signet rings, crested buttons, and armorial china. The company is run by my dear friend Hugh Macpherson, and he can be contacted via their website:

www.heraldicporcelain.com

Now, how about posting a picture of your arms?