There are some alternative manufacturers of relatively similar handlebars, even though some of them are even more expensive and thus not the answer the OP wants, some of them are cheaper.
(I give you only the names because links are not allowed by BSE).
Humpert Boomerang Handlebars - 25.4 mm Clamp
Halo Bar, found at TiCycles.
This unluckyly discontinued OEM titanium Halo Handlebar 22.2 that looks the same as the previous one.
I tried to search alternative names with no luck. Next best thing I can recomend that may give you similar hand positions are:
Moustache Bar
Butterfly Bar
If what you actually need is more space for accesories you can use one on this:
Problem Solvers handlebar accesory mount
This is the only comercially available product that I can mention, but I'm sure many others exist.
Depending on the type of accesories you need to mount you may be able to fashion DIY versions of this. Cyclocomputers, small lights, cellphone holders and similar are subjected to very small load, and can be perfectly mounted, for example on PVC tubbing, wich is very easy to paint black with spray paint to disguise the DIY factor.
PVC is very easy to work with, Can be cut and sanded with the same simple tools used for basic woodworking, and the 90 and 45 deg. elbows available are great for creating odd shapes.
Another source for DIY options is a hardware store. If you search google images for "conduit brackets" you'll see a lot of types of brackets used to hold pipes in place. Being a little creative and finding scrap pieces of tubing of the right diameter is all the other needed thing. You can, for example, attach a piece of tubbing parallel to the handlebar using clamps like these:
You can use strips of old inner tube to protect the handlebar from scratches, since these brakets are not very polished.
If you want to paint them, matt black anti corrosive spray paint gives a very good finish that kind-of resembles anodized black. Just use sandpaper to polish the brackets, wash them with kitchen soap to remove any grease and let dry before painting.
These brackets, properly combined can be firm enough to install bottle holders or heavier lights.
An advantage of these is that they are widely available, wich is an advantage when you mention touring since something may break while far from a specialized stores, but even small town hardware stores should carry pipe brackets.
(For example my commuting headlight is a tubular-shaped flashlight/torch held in place by means of two interlaced hose clamps. The clamps are looped one through the other in conventional-chain-like fashion. A strip from inner tube protects the handlebar and another protects the flashlight. The grip is so solid that I can perform some stunts or ride fast rocky descents and the light won't move at all).
Since many accesories come with adjustable mounting brackets, you have yet another option that is using handlebar extensions to gain more room to mount accesories. If your handlebar are the thin diameter (25.4 dia) you can mount the extensions very close to the center of the bar.
