Sadly we do not have a 3800 in stock to build ICCs with and we no longer truly support this decade+ old model. We have recently updated the ICCs on the 3880 and newer models of the printer though.
What I can do for you to get you started perfectly is offer two custom ICCs (the prestige and possibly a matte paper if you have Hahnemuhle Photo Rag) for this old model. I will share them on this thread and it should be useful to the rest of the community who use this model of printer. (These ICCs should also be good for general purpose matte/gloss printing on your printer.)
You can download the targets and instructions on this page. Custom ICC profiling Service | InkjetMall
Mail it in to the address listed and I’ll build the ICCs.
InkjetMall c/o Walker Blackwell
17 Powder Spring Road
East Topsham, Vermont