Found the solution, bit tedious work actually, but this solved my issue.

For anyone seeking the solution for the same, please refer the below link.

Bug when restore with the backup database not include filestore

Conclusion:

Was able to fix this problem with a workaround: manually going into the database and removing the entries pointing to the missing files from filestore

DELETE FROM ir_attachment WHERE store_fname LIKE '%<the ending hash>%'

For Example:

2016-05-06 09:07:25,787 1 INFO database-name openerp.addons.base.ir.ir_attachment: _read_file reading /var/lib/odoo/filestore/<database name>/82/825be0a9492aa429844218238d35347d6a3c9220
Traceback (most recent call last):
  File "/usr/lib/python2.7/dist-packages/openerp/addons/base/ir/ir_attachment.py", line 105, in _file_read
    r = open(full_path,'rb').read().encode('base64')
IOError: [Errno 2] No such file or directory: u'/var/lib/odoo/filestore/<database name>/82/825be0a9492aa429844218238d35347d6a3c9220'

So the above error would be fixed by doing

DELETE FROM ir_attachment WHERE store_fname LIKE'%825be0a9492aa429844218238d35347d6a3c9220%';

After doing this for every problematic file, Odoo re-compiled all the assets and the backend started working again.

P.S. For more detailed explanation, please refer the answer suggested by aisopuro in the above link.