A lot of responses but no one willing to stick there neck out a little so here it goes.....
I have a similar combination as you have and this is what I did. I originally had an Indy solid roller cam 268/264 @ .050 .659/.636 lift . This cam in my opinion is a little on the large side but still streetable. I never had any lash issues and drive this car frequently so I would not be concerned about any kind of maintenance or lash adjustments. With all that being said I recently converted over to Sequential port fuel injection and this cam works OK but does not generate enough vacuum to run in Speed density mode where I really want it to run.

My new "Street" cam is the one pictured below. The duration and lobe family I selected is aggressive enough to not give up to much of anything compared to the Indy cam but still have some lift to take advantage of the flow characteristics of the heads. The lobe separation angle is a little on the wide size but for me I need that to reduce overlap and build vacuum. I think this cam would work well in a carb application as well.

For valve springs in a street application with this lift I would select a really good endurance spring with at least a rate of 500 lb/in to no more than 550 lb/in and a seat load of at least 200 lbs to no more than 250 lbs,.... Generally speaking. The valvetrain will live a long life with minimal adjustments. The last set of Edelbrock heads I did I selected Howards Pacaloy P/N 98543 and installed them at 1.900 with 240 lbs at the seat and 600 lbs open. On my Indy heads with a taller installed height I have used Isky Special Process (SP) spring SP9365. There are other comparable options out there...

I would not even consider a flat tappet cam considering the issues with rounding the lobes and oil compatibility and just the quality inconsistencies out there with the success rate being hit or miss at best. I think a hydraulic roller in this application is not a good idea because the valve train is simply to missive to run the spring package necessary for the type of lobe lift these heads need to breath. The best thing you could do is invest in a quality set of roller lifters like Crower HIPPOS, BAM, or whatever the new flavor of the month is..... If the block is bushed than it may require a different style lifter as well depending if you want oil to the axle or not.

AG.