Enough interest was expressed in these sorts of resources to make a single thread with an extensive list of businesses to explore for what you're seeking. Enjoy!
***Notes in this color beside vendors are first hand/forum member reviews of companies***
Some tips and resources to help you on your cosplay building journey!
First of all, your budget will have a great impact on where and how you obtain your materials and pieces for your outfits.
If you have the tools (i.e. time, cutting mat and rotary blade, sewing machine, etc for making a tunic or pants) then I would highly suggest taking the time to go to a Joanns or similar type fabric store, browse their patterns section, find patterns that you like and narrow it down to the design you like, then looking for how much fabric it calls for and get it.
Keep in mind that you can use your measurements (if you feel comfortable) to tailor the outfit to be more form fitting if that is your desire. You can use newpapers and tracing skill to edit and make your own pattern based off of the premade pattern you selected and your measurements.
Making your own outfit will save you money in the fact that you aren't paying labor fees for someone else to build it, however it will take more of your time and much more effort to pull it off. But keep in mind that there is a great deal of satisfaction in learning throughout the process and coming out the other side with a piece that is one of a kind and you can say you made yourself. It's a great feeling.
That isn't to say that you can't outsource pieces that you don't have the tools to make (leatherworking, armor pieces, shoes, etc). There are some great small businesses that depend on niche consumers like us to keep them afloat and have unique and awesome talent!
If you wade through all of the copy cats on Etsy you can find some gems. Here are a few that I have utilized, and others that have merely caught my eye that you may find useful:
For unique belts/leatherworking:
Kradwear ***High Quality Custom Work***
ScandaloAlSole
WJWDesign
For unique clothing/shoes:
HoreHead ***High Quality Unique Pieces***
Punkktual ***High Quality Unique Pieces***
Runnickyrun ***Unique Leather Gloves and other apparel***
Dracolite
Eileen Wolan ***High End/Quality Premade Apparel - Reliable & Quick Ship***
Ayyawear/Verillas ***High End/Quality Custom and Premade Apparel and Shoes and Accessories***
Helmets/Masks:
TomBanwell
HeadShotProps
Oldjunkyardboutique
NokturnelEclipse
Needless to say there are a lot of places out there, and there are going to be a few that are right in your budget range.
I would highly suggest browsing the various lightsaber forums and SW cosplay forums - they all have very detailed and extensive tutorials and knowledge on how to make anything you need - many are budget builds, ways that people have found to save money - others are kind hobbyists who offer their services in areas you may not feel comfortable dabbling in or don't have the tools for - for example clothiers, armorers, leatherworkers, etc.
Linked here is an example of a detailed thread with links to tutorials and makers for Female Beskar'gam:
MMCC Fem Beskar'gam
And here is a link to a detailed thread of makers for costumes and SW costumes in general:
Saberforum Costume Buying Guide
I've basically done all of the searching around for just the bare bones of cosplay resources and information, but don't be afraid to browse and research and discover - that's how I've come across all of the information I've linked.
Enjoy the creative process and check out how others have been so successful at cosplay!
Good luck and happy creating!
Aletani
Feel free to add to this list of resources!