If you don't mind installing it, Python makes interactive socket use pretty easy. Here's an example of an interactive sessions with a HTTP connection, for demonstration purposes:
>>> import socket
>>> sock = socket.socket()
>>> sock.connect(("www.google.com", 80))
>>> sock.send("GET / HTTP/1.1\r\nHost: www.google.com\r\n\r\n")
40
>>> sock.recv(64)
'HTTP/1.1 302 Found\r\nLocation: http://www.google.co.uk/\r\nCache-Co'
For binary data you could just do something like:
sock.send("\xff\xfa\xfe\xf0")
The sockets API uses strings in Python, but as you can see it's pretty easy to send arbitrary bytes.
I can understand if you didn't want to install Python just for that (although it's got a pretty simple installer), but personally I think it's a reasonable tool for the job in this case - you've got all the flexibility of a powerful language there but you don't have to use it.
Alternatively you can get netcat for windows, which should be able to accept input from a file with redirect (which I'm pretty sure DOS supports). So, if you put your binary data into a file binary_data.bin
you could do:
nc hostname.org 1234 < binary_data.bin