I wonder if something more accessible, like meclizine, would have similar effects if made into a skin cream? I have tried One Skin for months and I really don’t see any effect. This would be a slightly different approach.
I would worry about consistency and dispersion of rapa particles in highly viscous ingredients at room temp.
I get crushed (Nano pulverizer) generic rapamycin filtered through a 80 μm mesh then dissolved in ethanol (Everclear 190 proof is easy to buy). I go to heated white petrolatum (Vaseline is easy to buy) at 40 degrees C with an industrial rotating mixer (2500 rpm) and then add rapamycin solution for 2 min then continue at room temperature for 8 min while reducing rpm to get ointment.