Yes it can be done.
Just a small point, by definition if you remove the OTA from a dob and mount it on an EQ mount it is no longer a dob. A dobsonian is a type of newtonian, so what you have then is a equatorially mounted newt.
Anyways, back to the question. Yes it can be done... but, there are a number of provisos:
1. At you correctly surmised a solid OTA of a larger dob will be heavy and will require an appropriate mount. Probably a 10-12" will need an EQ6 or equivalent as a minimum.
2. Most dobs are not setup for imaging. For visual use you can get away with a much smaller fully illuminated field, so the secondary tends to be smaller. So if imaging a new secondary may be required. Also many dob OTAs will display a fair bit of coma which would need a corrector (Paracorr or similar). Both these first 2 points apply especially to deepsky imaging rather than planetary BTW. Also the focal plane is usually inside or just outside the focuser, rather than where the sensor on a camera tends to be, necessitating either shortening the tube or moving the primary mirror up the tube.
3. Cost. All the above adds up top a fair bit of cost.
There is an article here
http://www.iceinspace.com.au/63-201-0-0-1-0.html on imaging with a plain dob and no EQ mount.
Cheers
Malcolm
PS. just so I am clear, I am not trying discourage you, just making sure you are aware of some of the pitfalls that you may encounter before you spend your hard earned cash!! If this the way you want to go then go for it!
Yes it can be done , what size is your OTA ? that dictates what size mount you will need , I do think that a 'Few Hundred' wont cut it , more like a 'Few Thousand" 
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:shi p2:
