Selcof or PDQ open mold bar system. Add the stacks you want. Buy extra spacers then buy longer bolts at the hardware store. PDQ sells the stack spacers extra if you need more.
The Selcof perfectly matches the Aeria Ultimate stems.
Search for my Felt DA topic on this forum to see pics.
If you want to go with a clipon bar/bullhorn/stem combo (for maximum customization), the Profile Sonic/Ergo 4525 can have up to 70mm of additional spacers added (130mm total pad stack). The aerobar is super-adjustable, which is great for dialing in you position. This also gives you the option of elevating the entire basebar/aerobar setup with different angle stems.
Note, I’m sponsored by Tririg, but the Alpha One is the gold standard for aftermarket bar adjustability. I actually used that Vision bar on my bike last year, and it’s a great bar, but after using the Alpha one with the monopost for almost a year now, I never want to go back to normal spacers. With a single bolt to adjust the height of the whole front end, and two exposed bolts for tilt, I find myself pretty constantly playing with my position because it’s so easy to swap back. There are also aero matched spacers if you need even more stack height and have the extra steerer tube length. There is also currently a 10% off sale on everything, bars included.
Kevin from Vision here. I would be happy to help answer any questions for you about the TFA bar or the SI013 bar, which is a similar system with out an integrated stem. Both will allow for up to 70mm of spacers be added.
as i age, my flexibility isn’t a good as before, so i need a setup where i have more adjustability in height when being in the aero position.
are there other alternatives out there either with or without aero stem that can do that?
Loads. What is your budget?
If you want to spend $$$ you can’t beat the Tririg for easy adjustability. But many inexpensive bars have stack spacers available. I think the Profile Aeria AL Evo is pretty slick bar that isn’t too expensive. I have the Felt Bayonet 3 with the full spacer kit and like it.
Here’s the Selcof in an old pic before I fixed the weird Felt DA spline stem mess with it at “full height” with the included spacers.
Here it is with the Aeria Ultimate stem: I’ve actually recently figured out how to run studs instead of bolts and use a standard Aerocoach tilt shim with the stack blocks to tilt the whole assembly. I don’t have pics of that yet.