Rowsons Transformers Pvt. Ltd.
Rowsons Marketing Private Limited - Service Provider of Transformers, Energy Saving Luminairies, Voltage Stabilizers, Switch Gears, Wind Solar Hybrid Products, Energy Conservation Products, LED Lights
http://www.indiamart.com/rowsons

Chaos Labs High Voltage Projects
High voltage projects including ignition coil driver, high voltage transformers, and a 60 kV pulse generator.
http://members.tripod.com/hvprojects/highvoltage/

Express Transformers & Controls Limited, Runcorn, Cheshire
Transformers up to 150kVA. Including reactors, inductors and ferrite (High Frequency) products also high voltage transformers, up to 80kVDC isolation and developing up to 60kVAC. From UK.
http://www.express-transformers.co.uk/

Hivoltrans Electrical
Manufacture EHV grade instrument transformers up to 245 kV, DC isolation transformers and high voltage testing transformers.
http://www.hivoltrans.com

R. R. Enterprises
High Voltage Transformers, Transformers, Ignition Transformers, Epoxy Moulded H. V. Transformers, Low Voltage High Current Transformers, Isolation Transformers, 1 Phase Transformers, 3 Phase Transformers, India
http://www.rrtransformer.com/

Dakota Transformer
Distribution transformer for industrial use. High voltage transformers, single - three phase power transformers, transformer repair, buy and sell.
http://www.dakotatransformer.com/

D&M's High Voltage, Inc.
Manufacture specialty single and three phase transformers - high current, high voltage, zig-zag, phase shifting, autotransformers, isolation, rectifier, inductors, reactors, saturable reactors, and AC/DC power supplies.
http://www.dmshv.com/

Ashita Techno Enterprise
Leading manufacturers of transformers, Mumbai.
http://www.ashitatechno.com/

Chirk Industry Co., Ltd.
Manufacturer of high voltage transformers, high voltage switching power supplies, negative ion generators, ozone generators, and electrostatic precipitators.
http://www.chirkindustry.com

Using multiple transformers to get more high voltage power
An interesting paper on how to combine HV transformers to get much higher voltages.
http://home.earthlink.net/~jimlux/hv/xfrmr1.htm