Moving wagons is not cheap, they can travel like most vehicles on a car trailer or similar and this includes overseas.
Currently we can ship to say France or Spain for approximately £2-3,000, this will depend on the actual wagon, times of year and a third party courier we use. Be aware that EU VAT taxes will apply for an export.
There are also a number of Roll On Roll Off services available. Mostly sailing from Liverpool or Southampton, cars, caravans and motor homes can be cost effectively shipped for a basic cost again in the region of £3,000. However as ports and shipping companies tend to lack spare horses for moving such items, they would have to be mounted on a car trailer. A new car trailer would start at about £3,000 and obviously it would have to be compliant with trailer specs in your country. We could source decent used ones for about half of this figure. The trailer is an expense you can recoup if it is not required once your wagon is delivered.
Every countries customs have their own rules. Australia would certainly insist that an old wooden item is fumigated, this is something the shipper can arrange for you, usually done in the UK with an appropriate certificate issued. Also shipping to the USA requires a registered US shipping agent at the port of arrival, again the shipper can arrange this, but it is unfortunately an additional expense.