Are 2.26 GHz and 2.53 GHz processor logic boards interchangeable?

I have a mid 2009 13" Macbook Pro (A1278) MacbookPro5,5. My logic board has clearly been failing for quite some time now so I am planning to swap it out for a new one as it is significantly cheaper than buying a new laptop all together. I wondering If I can use the 2.53 GHz processor logic board from the same year instead of the 2.26 GHz. In the link below it shows them both as being parts for this upgrade but doesn't specify if they are interchangeable. They appear to the same shape. And when I looked the 2.53 model up online is says:

Compatible Model(s): MacBook Pro 13.3" 2.53GHz Core 2 Duo (MB991LL/A, A1278, MacBookPro5,5) - Mid 2009

I just want to be sure it will work before I order the part.

MacBook Pro 13" Unibody Mid 2009 Logic Board Replacement

Thanks for your help!

P.s.

Where do you buy more of the little black (phillips 00) screws that are used for almost everything inside this laptop? Ive seen plate screws, hard drive screws and keyboard screws online, but none of them look right to me.