Refused mortgage because of default

Hi

I am based in N.Ireland and have been refused a mortage with the Nationwide/Progressive because of two defaults in 2008.
Amounts are £1566 and £230

I earn 34k and have a deposit of 20% on a house £165k.

Is there anywhere else I can turn? Student overdraft and store card over 4 years ago are coming back to haunt me!!!

Any help would be appreciated

Thanks