A heavy hearted no from me, for reasons outlined already by PhilPub and Chris2304. However, we should always look to the mote in our own eye: our athletes that get caught usually try to bluster their way out of it too, though I don't believe there's any similar, state-sponsored widespread programme here.
I think, quite apart from anything else, running shoes have got so expensive in recent years (the cynic in me says that the explosion of interest in running is being exploited to the maximum, though Beer and Curry Runner might say otherwise) that it's absolutely the minimum that a running apparel shop offers excellent customer service. I tend to buy online because I know what I want and it's easier to get cheaper deals with end of line stuff and so on.
Not technical advice, but I would say that you shouldn't be scared (not saying you are, but you might be) of the jump in distance - I personally think a half marathon is within anyone's range with a modicum of training, whereas a marathon or beyond starts doing things to your body that you have to be prepared to cope with and won't experience in a half. That's not saying a half won't hurt at some point - it will - but it won't start eating into your energy reserves in quite the same way as a marathon does. And don't obsess overly on time - you're taking a small step into the unknown and in the first one are setting a marker for the next one, finding out a bit more as you go about how to pace yourself, and what are achievable start, intermediate and finish paces. Some might disagree, but I think it pays to be a little conservative in the first couple of miles and upping the pace only if you feel ok with it. You might be wary of how long you'll be on the road, but you might actually be surprised how quickly it all goes. If you really DO have a time in mind, find out if the race has pacers - they're usually experienced runners who will keep to the necessary pace and can be helpful (or not, if they simply disappear up the road and you can't respond!).