The symbol for megahertz is MHz, m is for milli. Hz is Hz, never hz.
Do you want a crystal or an integrated oscillator? A bare crystal requires an
oscillator circuit and you need then to know if its series or parallel resonant and
what load capacitance its designed for.
What tolerance are you looking for - there are various grades of quartz crystal so its
important to get one thats within spec for your application. You won't get 15 digits of
precision from any crystal, expect 5 at best.
The other approach is to use a stock 10MHz crystal into a clock generator chip
(a programmable PLL, basically), but that could have issues if phase-noise is
important to your application.
So tell us what the application is and you will probably get more definite advice.