After examining various sites, you will have realized that, in absolute, the prices are quite high.
For this reason and, considering that the very high level of workmanship has a major impact in the cost of the instrument construction, a few enthusiastics took their initiatives to study a project and to put on sale their constructional drawings and related instructions. The following are a few examples:
John Smith is a brilliant british designer who has introduced a de facto standard with its 20 note Busker crank organ. In the site of his agent, www.rollcutter.com , you can buy both the design plans and the more difficult to build components, besides the music rolls. You can choose among different organ models.
www.castlewoodorgans.com is an Australian designer and buider who sells the kit of a busker organ similar to the one of J.S., of which it has adopted the standard of the music rolls.
Other places support the J.S. organ, for example you may enter the Melvyn Wright site, well known professional british arranger, (www.melright.com/busker/index.htm)
who , besides offering music rolls, dedicates plenty of space to a collection of articles, suggestions and photo gallery thanks to materials sent by people who have built the busker project. (each published article receives as award a complimentary music roll)
You may find up there also an article of mine, dealing on costs and value of the Busker.(Thanks again for the music roll Melvin!)
A further crank organ kit proposal comes from this german constructor:www.drehorgelbau-schlemmer.de/bausatz.htm
Another instrument worth to be considered, even if of higher class, is the Wurlitzer 105. This is a machine classified as "Band Organ" i.e. the instruments that at the beginnnig of the past century, where utilized as sound track in skating rings or in the merry go rounds.There is a web site supporting the " Wurly105", and there is a site where you may buy the most difficult to find components among which the pneumatic valves and the original rolls tracker mechanism. The results of some Wurlitzer 105 restorators or rebuilders can be admired in the site www.carousel.org in which you may find two series of a dozen of articles each respectively on the restoration details and the selfconstruction of the instrument. The first one is written by Dr. Bill Black, one of the top Band Organs expert, the latter is written by Howard Wyman, a retired electrotechnical engineer.
Then Robert Stanoszek offers, for 40 $ only, the construction drawings of a Band Organ, the tuning instructions and the addresses where to find the main components. The site is: http://calliopeplans.com
Recently Yahoo has opened a Group for the fans of the Wurly 105 which utilize the di Stanoszek plans, on the site: http:/groups.yahoo.com/group/wurlitzer105
Another example of self built organ that really wondered me is the one you can find on the site of James Anderton www.organeze.freeserve.co.uk/index.html. The author tells that in his late seventyes has decided to design and build, starting from scratch, a band organ MIDI driven, which can utilize EPROM cards to memorize the music. The instrument, named Organeze, is very interesting with a large number of notes and pipes. The author makes available the essential data of the project and supplies directly the electronic board.
If you do not have the skill to build everything, but are keen to put together subassemblies, Alan Pell, a well known U.K. manufacturer, offers a wide range of organ subassemblies and components on his site www.alanpell.com. With these components, instruments of various sizes can be realised.