You can see pictures of 73107 at the Hastings Diesel site ... there are some nice ones of it on a test run at:
http://www.hastingsdiesels.co.uk/news/articles/2007a06/
The copyright / hotlink issue is a bit of a minefield, and one that's caught me out in the past. It's very easy to think that you're clear to include the URL of an image in your page so that it loads there when (in fact) you may not be, and it's also easy to duplicate an image to other's space when you're not legally supposed to do so. Sometimes - as in this case - it's very hard to tell and there are grey areas.
Initially, respponsibility lies with the poster and indeed everyone has signed up to the forum agreement (before they could post) which passes responsibillity to them for what they post. However, once a post which may not be within copyright (or some other) law is brought to the site operator's attention, a degree of responsibility in law shifts to him/her if (s)he does not check and act as appropriate to return the site content to something that's within the rules.
The picture of 73107 is a very grey area. I'm 100% sure it was posted with the best of intent. But I also know that there are certain images which are often hotlinked from my (work) web site quite often ... and copied quite often too, I know how I trace them, I know what I can (and very occasionally DO do) if I find them elsewhere in this way, and (sorry) I don't have the time to risk finding myself in the firing line over a picture of an electrodiesel
If you want to see 73107 ... please follow the link above to the Hastings Diesel site. She's a lovely loco, and you can enjoy many pictures of her (and the narrow bodied stock with was not at Paddington the other day) on that other site.