Only had the time for a quick look but pedigree's that feature both your dogs sire (sires side -
Cracking Idea At Redfox) and grandfather (dams side -
Marshell Of Eureka Xpinx) feature in pedigree's on Champdogs. I think these would be your best bets for looking for related stock. Maisey Bella will be virtually impossible to trace as the name has no affix and as far as I can see nothing strong affix wise in her pedigree. You would need to get really lucky to find her owner or someone who knows the bitch.
If you use the search facility on
Champdogs Home Page you may be able to track active decedents for both the named dogs above.