When in doubt, dont.. Going by your post, it seems you are only worried about maintenance/parts, everything else is ok with you. And RD is definitely not for you if you are worried about maintenance. You need to have a lot of good reasons(excuses rather) to buy an RD today i.e. 2-3 decades after its launch.

Buy the C350.

RD 350 anytime over the RE, coz you have decided to go vintage, then go for the best. Still the RD is a Blockbuster in India and has a Cult status.

Offcourse the RE too has it too, but not as best as RD.

Regarding Spares, you get them still in Yamaha through pre-order and also many shops here at Chennai sell non-branded parts for the RD. I know a guy who recently re-built his RD from scratch.

Supreeth,
It all depends on your needs bro..

If you are into performance GO FOR the RD..!! Nothing, and I mean NOTHING beats the RD in terms of Performance and Feel (combined)

If you tour a lot, Get the Bull..

1 suggestion: If you have enough money and can hold back for sometime,

Get the RD NOW (You'll never regret, IF you have the Money ), as its already scarce, later you can get the Bull (Book it now, you shall get it in SOME time(months))..

What to do with Pulsar is your decision! If you are rich enough, keep it (very good for city).

Just my personal opinion!

No question on RD350 and is much better choice among the two if you want a performance oriented. At the same time, I would not advise to buy RD350 at this era. Ask yourself if you want to ride your bike during the weekend or spend time in garage.

Next is spares, I tell you, later released Yamaha 2 strokes models (RX) have a huge scarcity for spares. RD is much more older, so think even digging would not help, you'll need to do some borewell.

Even if they are available, you should be medically fit to take the shock when you are told the price tag.

Having said all, if you still want to go about RD350, a small advise, do a scan in the market in and around your place to learn about the spares availability. Least if you are half way purchasing all the spares and suddenly changed your mind, there will be ready buyers for RD parts. So you are in WIN-WIN situation. However, if you invest in bike which will not come dear, then giving up the restoration project would be a costly idea, unless you want it that way.

Duke 200 may launch shortly but go for CBR...