Thats admirable, but if you’re that tight on bugdet, I think it’s perfectly fine to go with the more affordable option. (You could probably upgrade it later by mail)
It’s unlikely that the campaign-preordering runs longer than december, as they’ll have to place the production order soon. It has also been suggested that prices might go up a little at some point. It also remains to be seen if monitor bundles make it into the regular shop.
Last but not least, there’s a slight chance you’ll have to pay import taxes: