If in no hurry to add stock then get some rock now and some later if you just want something to look at.
I love the drs too and they average around $4 a lb shipped. You will have a mini-cycle again every time you add new lr
but as long as there isn't stock it isn't an issue.
You could get away with 30% lr
and 70% base IMO
. It won't look as pretty but base rock will provide bio-filtration within a month or two and will still all "look" like the live rock within a year or two.