The only thing would need to be - is to match the loop frequency of the Carrier oscillator - that 5.12MHz "secondary clock" that 10.240 is halved into.
Then the matching is simply the parsing - start with the base - then divide by two - and hope like h*ll the coils will allow the loop to the range or extent of the spread you want. (That is if you're into Cobra 29's, 25's or the PC series of 66/68 and 76/78 series.
So, in the SSB realm they changed the samplers
Transmission1.net has (or had) something like this endeavor for trying to make the clarifier undriftable. But the problem then lies in the base clock you reference to - being the original 10.240MHz - which - if it drifts, the means to undo that drift depends on the clock references used - ad infinitum ad nauseum.
So in a way, you kind of have to see what others did to offset such a wide bandwidth - so to see the RF switch used in one fashion to work like a ripple filter (slow down) and then paralleled across - to narrow down the rather wide influence was a unique approach to handle the bandwidth, but could NOT offset the drift due to the tolerance issues it requires in free-item or parts as discrete and their package outlines.
So to bring up SMD - it may help but to make it a drop in is not an easy task for say the Cobra 148 uses 7.8MHz and a Tripler while the Cobra 146 (Uniden style) uses a 10.69x with no Tripler - and you still have the drifting amongst the analog realm - so when your PTC or NTC or just plain NOS because you use NPO - you still in a realm of some that act like POS - even though much of the tolerances of the SMD have improved.
I only mentioned the "dual varactor" because of all its faults, has earned the respect of and the distaste for, some that have worked over analog versions of what is now integrated technology
