With no calibrated gear it becomes a chicken and egg type of thing you still need an 'Accurate' Reference to make that Transfer Standard. So your choices are buy or make the best one you can.
Vref best options without going broke.
1 - Buy an AD-584 with measurements attached. With no measurements it is no better than your current best meter for Accuracy.
2 - Build a MAX6350 based reference and make it YOUR volt. It wil be better than just about any 4.5 digit meter I am aware of for initial accuracy?
3 - There is 399 Refs in the for sale section at present for not to many $$ but I am not sure of what there long term aging or stability is as I haven't looked at the project other than a glance in the for sale section? Personally I would stay away unless you already own a meter capable of tracking and looking at its drift (6.5 digits)
4 - DMM check or similar other devices are also available online.
How you get to the various voltage points to transfer YOUR Volt from there is a topic in itself and really to large for here and outside basic dividers and not Beginner material in particular. Depending on the meter you want to Cal as I put a few posts back you need to hit a huge number of different points even for a couple of meters. This is why I own a couple of Calibrators both AC and DC to 1000V+ but they are not sensible for most apart from their boat anchor dimensions as per the photo below.
One other possible option is you go down the path Ian Johnson has with his LM399 based Reference
http://www.ianjohnston.com/index.php/onlineshop/handheld-precision-digital-voltage-source-v2-detail using a good quality DAC/micro on the reference but this is way out of Beginner level and will cost real money.
Back shelf is how to go 'part' of the way into the rabbit hole 7.5 digit Advantest on the top shelf, HP735A, Fluke Null meter, Fluke Portable Calibrator, Bottom row HP 740B working but mid renovation 1000V DC Calibrator/Null meter and Valhalla 1200V AC Calibrator. Won't mention my 'slight' time nut addiction either. Plus other assorted 'stuff'. No I don't feel I have a problem because TEA assures me I am 'normal'
![Grin ;D](https://www.eevblog.com/forum/Smileys/default/xgrin.gif.pagespeed.ic.QVVz6XIT20.png)
Yes I am showing off the toys a touch
![Wink ;)](https://www.eevblog.com/forum/Smileys/default/xwink.gif.pagespeed.ic.cldandycH0.png)