Firstly, Homage is not quite so rosy these days!
It was re-formulated, but suggest trying before buying as it may have improved again!
Amouage do several rose attars (Itrs).Harrods used to have a good range and certainly used to post from available stock within the U.K.
The Amouage Lowndes Street Boutique has access to a good variety, so suggest a 'phone call if you are in the U.K.
I have the old white box version rose attar, then just sold as 'Rose', which I am fairly sure was made from Bulgarian rose.
New versions may be different, they were recently doing a Turkish & a Ta'ifi as well.
The prices range from o.k., to painful!
I think that the traditional Rose attar (Itr) that you might be thinking of is rose distilled into sandalwood, but other people should be able to add to this!
Otto is just another name for the steam distilled essential oil & does not last very long on the skin or smell like Itr oils as it is an ingredient, rather than a finished product.
There are various branded Bulgarian otto-based scents, but they may have an alcohol base - the one that I have does.
Again, someone may know one that doesn't.
These people have a good selection and turnover of high quality oils & absolutes & will give you a good idea of prices that you will expect to pay for a good product - but they are not 'finished scents' intended to be used straight on skin & the one in your link is not either, so just a comparison.
See this article
Surrati (K.S.A.) do a Wardh Taifi oil, which may not be 'pure', but lasts fairly well and is remarkably well-priced at about $30 for 1/2 tola.
It is not easy to obtain and I don't know of a U.K. supplier - if anyone else does, please share!
There are many low quality 'attars', Itrs and essential oils on sale over here.
Good luck & please let us know how you get on