Apparently it has the same footprint as the URSA, so anything that can fit the URSA can fit the ROC-DS. According to https://scdata.io/ship-cost-uec-dollar-ratio/ the cheapest AUEC option is the Constellation Andromeda.
Star Citizen
~~Can anyone confirm that it will fit in the Nomad?~~
There's a whole: Will it fit? Guide here: https://robertsspaceindustries.com/spectrum/community/SC/forum/3/thread/will-it-fit-ship-amp-vehicle-guide-3-17-4
Looks like there's a trick to getting it to fit in the nomad.
Edit: It will fit, but you can't raise the back.
You could probably rent it cheap for a day just to verify. Looks like the ship sells for a little under 1mil aUEC at Lorville: https://starcitizen.tools/Nomad#Universe_availability
Otherwise you could fit it in the Freelancer Max which goes for a little over 2mil aUEC.
Other ships it fits in: Valkyrie, Corsair, Constellation (Taurus and Andromeda), MSR, HH, Hercules, 600i, 890J.
Can you elaborate why you like the DS more? Are you with a buddy, or do you switch seats whenever you found a cluster?