Hi, well this isnt a question I get asked too often!! :)
There doesnt seem too be much in the way of an FX market between Turkey and Georgia, or at least we dont get many contributors towards it - except the one you have picked - which is the National Bank of Georgia rate and updates very regularly throughout the day.
The only other rates we have are his chain, which provides a list of calculated FX Cross Rates (we calculate these off TRY= and GEL= rates): GELX=
and this chain which provides a list of contributed crosses (we create these when we get more than one contributor: GELX1=
So id say the one you have picked is your best bet.