From the dealer, definitely a grey area... The 300's are not
sold by KTM as EPA/DOT compliant, and therefore not
street legal as sold by KTM. But they also don't (or didn't a year or two ago) say "off-road use only" on the title. Evidently some dealerships have had good luck with just submitting the title paperwork and having CO DOT issue a title, not differentiating between the truly street legal KTM dirt bikes (450/530 EXC's) and some of their other bikes.
But even if that doesn't work, in Colorado it is relatively easy and inexpensive (though not as easy as it was a few years ago) to take an off-road bike and get a title/plate for it. This thread
has more info than you could ever dream about on the subject! While the process seems to differ a bit depending on which State Patrol barrack does the inspection, in summary you: Add DOT tires, horn, reflectors, brake light, tail light, headlight, mirror, print out some forms, get it inspected by State Patrol for VIN and compliance, bring everything to MVD and if you jumped through every hoop perfectly the first time
, get your title and plate! Evidently getting an appointment and consistent application of the rules with the State Patrol is the biggest hassle...
This route, however, can not be done by the dealer directly, but only by the owner. Ironically, the thing that makes it sometimes possible for dealers to semi-legitimately title a KTM dirt bike causes problems with the legitimate process. The title or bill of sale MUST SAY for off road use only! So if the title does not, make sure the bill of sale does, and leave the title at home when you go to MVD.